Seasonal and Age Dependent Variations in Meat Yield of Abu Mullet (Planiliza Abu (Heckel, 1843)) from Orontes River
Total Page:16
File Type:pdf, Size:1020Kb
Seasonal and age dependent variations in meat yield of abu mullet (Planiliza abu (Heckel, 1843)) from Orontes River Gülnaz ÖZCAN*, Ayhan ALTUN, Berna Funda ÖZBEK İskenderun Technical University, Faculty of Marine Science and Technology, Hatay, Turkey. *Corresponding author: [email protected] Abstract: Investigation on the seasonal and age dependent meat yield of Planiliza abu has been carried out on 299 specimens collected from Orontes River between April 2012 and March 2013. Analysis of meat yield was based on the calculation of the ratio between the body weight and the weight of organs or body parts e.g. head, fins, and internal organs. Average meat yield was found to be 65.51% and head weight was 16.54% of the body weight. Weight ratios of fin, internal organs and other parts including gonads of the fish to body weight found as 2.47%, 11.74% and 3.74%, respectively. Age dependent average meat yields have varied from 63.34% at age 0 to 70.68% at age IV. Therefore, it can be concluded that average meat yield (productivity) increases with the age. Seasonal productivity was minimum in winter (63.16±1.51%) and maximum in autumn (66.41±0.43%). Moreover, there were strong correlations between body weight and head weight, and the weight of internal organs, and meat yield, and correlations were determined as 0.9283, 0.8354 and 0.9668, respectively. Keywords: Planiliza abu, meat yield, Orontes River, Hatay. Introduction inhabiting Orontes River Basin. Abu mullet, Planiliza abu, is the only freshwater representative of this genus. Besides Euphrates and Tigris Materials and Methods Rivers, P. abu is found in Orontes River (Özcan, 2013). This study was carried out using specimens collected This species is an exotic (alien) species for the River monthly for 12 months from April 2012 to March 2013. Orontes and Yalçın-Özdilek (2003) claimed that this Specimens were collected either by electrofishing or using species introduced to this river by human around the year fishing nets. Specimens were transported into the 2000. In addition, it is commercially important due to its laboratory prior to length and weight measurements. Fork high economic importance (Abd et al., 2009). lengths of the specimens were measured with 1 mm The Orontes River (Asi in Turkish and Arabic) is the precision. Likewise total weight (TW), head weight main river draining to the Levant coastline of the (HW), internal organ weight (IOW), gonad weight (GW) Mediterranean Sea. The Orontes River is an important and fin weight (FW) were measured at 0.01 g precision freshwater resource of the Eastern Mediterranean region using a sensitive electronic scale. and 380 km long in total. The river rises from Lebanon Dissection and weight measurements of the body parts and crosses Syria before running into the Mediterranean and organs were carried out after scaling of specimens Sea in Samandağ, a town of the Hatay Province, Turkey. intact. Internal organs except gonads were weighed The length of the river in Turkey is 94 km and it passes following abdominal dissection of the specimens. through Antakya (Antioch), the central town of Hatay. Dissection of heads and fins were also realized The tributaries of Orontes River are Karasu, Afrin, Büyük meticulously for measurements. Carcass weight was Karaçay and Küçük Karaçay streams in Turkish determined by weighing fish remaining after the boundaries (Özcan et al., 2012). The aim of this study is dissection of body parts and organs, and meat yield (%) to provide information on the meat yield of P. abu was calculated by determining the ratio of the weight of 67 ACTA BIOLOGICA TURCICA 29(2): 67-71, 2016 Table 1. Descriptive statistics of weight of Planiliza abu. Measurements Ratios Min Max Mean±SD TW (g) 0.30 66.40 11.79±0.71 HW (g) 0.06 9.35 1.68±0.09 FW (g) 0.02 1.91 0.32±0.03 CW (g) 0.20 44.5 8.70±0.69 IOW (g) 0.02 9.75 1.53±0.10 Fork Length (cm) 3.7 18.5 10.0±0.20 HW/TW (%) 8.19 30.43 16.54±0.40 FW/TW (%) 0.82 6.67 2.47±0.12 IOW/TW (%) 3.64 27.17 11.74±0.25 Meat Yield (%) 46.15 75.38 65.51±0.69 CW/TW Table 2. Age dependent meat yield and proportions of body parts and organs of Planiliza abu. Age N HW/TW IOW/TW GW/TW FW/TW Meat Yield % % % % % 0 80 19.88±0.36 9.75±0.43 4.64±0.68 2.39±0.08 63.34±1.37 I 91 16.40±0.24 12.23±0.47 3.96±0.29 2.40±0.06 65.01±0.71 II 85 14.74±0.31 12.67±0.44 3.07±0.47 2.61±0.14 66.91±0.93 III 41 14.17±0.38 12.63±0.69 3.38±0.66 2.70±0.05 67.12±0.51 IV 2 14.12±0.65 12.12±0.75 0.59±0.39 2.49±0.12 70.68±1.21 carcass to the weight of the whole fish. Otolith reading was performed to determine the age of fish. Sagittal otoliths of specimens were cleaned with distilled water, and then, placed in a petri dish containing 1:1 distilled water and glycerin. Age reading was carried out using stereomicroscope equipped with the overhead light. Descriptive statistics; minimum (Min) and maximum (Max) values, mean (M) and standard deviation (SD) of analyses has been given in Table 1. Results Figure 1. Age dependent meat yield and proportions of body part of Planiliza abu. The proportion of the body parts and organs revealed that head comprised %16.54 of total weight (Table 1). Internal of P. abu increases with the age (Table 2). organs, gonads and fins were %11.74%, 3.74% and 2.47% Seasonal variations in the meat yield and proportions of the weight, respectively. Remaining 65.51% was the of body parts of P. abu inhabiting in Turkish part of meat yield of P. abu. Orontes (Asi) summarized in Table 2. Accordingly, Age dependent average meat yield of the individuals seasonal variation in meat yield (between 63.16% in of P. abu varied between 63.34% for age 0 and 70.68% for winter and 66.41% in spring) was similar to that of the age IV and it was vise versa for head weight ratio with head weight/total weight (16.03% and 17.71%, 14.12% for age IV and 19.88% for age 0 (Table 2). The respectively). The rate of internal organs was the highest proportion of the internal organs was the highest (12.67%) (15.24%) in spring and reached to the lowest value at age II while it was the lowest (9.75%) at age 0. FW/TW (9.61%) in autumn. In contrast, the proportion of the ratio ranged from 2.39% (age 0) to 2.70% (age III). The weight of fins to total body weight was the lowest (2.36%) proportion of the gonads was the most fluctuating in spring and the highest (2.65%) in autumn. The ratio of parameter. It was 4.64% of the total weight at age 0. the gonads was the most fluctuating parameter as it was Whereas the lowest value for gonad weight ratio (0.59%) the same in age dependent proportions. The results of was obtained at age IV. Figure 1 shows that the meat yield seasonal variation regarding the ratio of gonad weight 68 Özcan-Seasonal and age dependent variations in meat yield of abu mullet of Cobitis avicennae Table 3. Seasonal variations of meat yield and proportions of Planiliza abu. Seasons N HW/TW IOW/TW GW/TW FW/TW Meat Yield % % % % % Spring 56 16.09±0.48 15.24±0.59 0.43±0.65 2.36±0.05 65.88±0.43 Summer 62 16.50±0.30 11.93±0.65 4.23±0.81 2.37±0.11 64.97±0.91 Autumn 71 17.71±0.38 9.61±0.45 3.62±0.33 2.65±0.45 66.41±0.43 Winter 110 16.03±0.37 11.22±0.26 7.06±0.27 2.53±0.06 63.16±1.51 fish species of Turkey (Table 4) such as Barbus capito pectoralis (Duman et al., 2003), Chondrostoma meandrense (Özcan and Balık, 2006), Capoeta bergamae (Şaşı, 2009) and Capoeta umbla (Kurt-Kaya et al., 2013). However, Zencir and Korkmaz (2004) reported a higher average meat yield for Tinca tinca. Meat was considerably lower for Alburnus orontis (Bozkurt et al., 2006), Oncorhynchus mykiss (Aydın et al., 2009), Squalius cephalus (Karaton and Gürel-İnanlı, 2011), Capoeta trutta (Kurt-Kaya et al., 2013) and Carassius gibelio (Dağtekin Figure 2. Seasonal changes in meat yield and proportions in and Baştürk, 2014). Differences in average meat yield can Planiliza abu. be attributed to the species, habitat and available revealed that the gonads were almost empty (0.43% of the resources. Nevertheless, meat yield was usually found to total weight) in spring and reached to 7.06% in winter be more than 50% of total weight of the species except in (Table 3). the case of C. gibelio. Based on the results, the seasonal variations in the It was found that the meat yield of P. abu increased proportions of fins and head were rather low in compare with the age and varied from 63.34% at age 0 to 70.68 at to the variations in the meat yield and the rate of internal age IV.